The synthesis of biologically active indolocarbazole natural products.

Covering: up to 2020The indolocarbazoles, in particular indolo[2,3-a]pyrrolo[3,4-c]carbazole derivatives, are an important class of natural products that exhibit a wide range of biological activities. There has been a plethora of synthetic approaches to this family of natural products, leading to advances in chemical methodology, as well as affording access to molecular scaffolds central to protein kinase drug discovery programmes. In this review, we compile and summarise the synthetic approaches to the indolo[2,3-a]pyrrolo[3,4-c]carbazole derivatives, spanning the period from their isolation in 1980 up to 2020. The selected natural products include indolocarbazoles not functionalised at indolic nitrogen, pyranosylated indolocarbazoles, furanosylated indolocarbazoles and disaccharideindolocarbazoles.

Lower resting and exercise-induced circulating angiogenic progenitors and angiogenic T cells in older men.

Aging is associated with a dysfunctional endothelial phenotype as well as reduced angiogenic capabilities. Exercise exerts beneficial effects on the cardiovascular system, possibly by increasing/maintaining the number and/or function of circulating angiogenic cells (CACs), which are known to decline with age. However, the relationship between cardiorespiratory fitness (CRF) and age-related changes in the frequency of CACs, as well as the exercise-induced responsiveness of CACs in older individuals, has not yet been determined. One-hundred seven healthy male volunteers, aged 18-75 yr, participated in study 1. CRF was estimated using a submaximal cycling ergometer test. Circulating endothelial progenitor cells (EPCs), angiogenic T cells (TANG), and their chemokine (C-X-C motif) receptor 4 (CXCR4) cell surface receptor expression were enumerated by flow cytometry using peripheral blood samples obtained under resting conditions before the exercise test. In study 2, 17 healthy men (8 young men, 18-25 yr; 9 older men, 60-75 yr) were recruited, and these participants undertook a 30-min cycling exercise bout at 70% maximal O2 consumption, with CACs enumerated before and immediately after exercise. Age was inversely associated with both CD34+ progenitor cells ( r2 = -0.140, P = 0.000) and TANG ( r2 = -0.176, P = 0.000) cells as well as CXCR4-expressing CACs (CD34+: r2 = -0.167, P = 0.000; EPCs: r2 = -0.098, P = 0.001; TANG: r2 = -0.053, P = 0.015). However, after correcting for age, CRF had no relationship with either CAC subset. In addition, older individuals displayed attenuated exercise-induced increases in CD34+ progenitor cells, TANG, CD4+, TANG, and CD8+CXCR4+ TANG cells. Older men display lower CAC levels, which may contribute to increased risk of cardiovascular disease, and older adults display an impaired exercise-induced responsiveness of these cells. NEW & NOTEWORTHY Older adults display lower circulating progenitor cell and angiogenic T cell counts compared with younger individuals independently of cardiometabolic risk factors and cardiorespiratory fitness. Older adults also display impaired exercise-induced mobilization of these vasculogenic cells.

Assessing the detection of human papillomavirus late mRNA in liquid base cytology samples for risk stratification of cervical disease.

Molecular human papillomavirus (HPV) testing is an important and developing tool for cervical disease management. However there is a requirement to develop new HPV tests that can differentiate between clinically significant and benign, clinically insignificant infection. Evidence would indicate that clinically significant infection is linked to an abortive HPV replication cycle. In particular the later stages of the replication cycle (i.e., production of late messenger (m) RNAs and proteins) appear compromised. Compared to current DNA-based tests which indicate only presence or absence of virus, detecting virus mRNAs by reverse transcriptase PCR (RT-PCR) may give a more refined insight into viral activity and by implication, clinical relevance. A novel quantitative (q)RT-PCR assay was developed for the detection of mRNAs produced late in the viral replication cycle. Initially this was validated on HPV-containing cell lines before being applied to a panel of 223 clinical cervical samples representing the cervical disease spectrum (normal to high grade). Samples were also tested by a commercial assay which detects expression of early HPV E6/E7 oncoprotein mRNAs. Late mRNAs were found in samples associated with no, low and high grade disease and did not risk-stratify HPV infection. The data reveal hidden complexities within the virus replication cycle and associated lesion development. This suggests that future mRNA tests for cervical disease may require quantitative detection of specific novel viral mRNAs.

Expression of mRNA for galanin, galanin-like peptide and galanin receptors 1-3 in the ovine hypothalamus and pituitary gland: effects of age and gender.

The neurotransmitters/neuromodulators galanin (GAL) and galanin-like peptide (GALP) are known to operate through three G protein-coupled receptors, GALR1, GALR2 and GALR3. The aim of this study was to investigate changes in expression of mRNA for galanin, GALP and GALR1-3 in the hypothalamus and pituitary gland, of male and female sheep, to determine how expression changed in association with growth and the attainment of reproductive competence. Tissue samples from the hypothalami and pituitary glands were analysed from late foetal and pre-pubertal lambs and adult sheep. Although mRNA for galanin and GALR1-3 was present in both tissues, at all ages and in both genders, quantification of GALP mRNA was not possible due to its low levels of expression. mRNA expression for both galanin and its receptors was seen to change significantly in both tissues as a function of age. Specifically, hypothalamic galanin mRNA expression increased with age in the male, but decreased with age in the female pituitary gland. mRNA expression for all receptors increased between foetal and pre-pubertal age groups and decreased significantly between pre-pubertal and adult animals. The results indicate that the expression of mRNA for galanin and its receptors changes dynamically with age and those significant differences exist with regard to tissue type and gender. These changes suggest that galaninergic neuroendocrine systems could be involved in the regulation of ovine growth and or the development of reproductive competence. The roles played by these systems in the sheep, however, may differ from other species, in particular the neuroendocrine link between nutrition and reproduction and GALR1's role in pituitary signalling.

Expression of cell cycle associated proteins cyclin A, CDK-2, p27kip1 and p53 in equine sarcoids.

Equine sarcoids are benign fibroblastic skin tumours affecting equids worldwide. Whilst the pathogenesis is not entirely understood, infection with Bovine Papillomavirus (BPV) types 1 and 2 has been implicated as a major factor in the disease process, however the mechanism by which BPV infection contributes to sarcoid pathology is not clear. In this study, we show that the majority of sarcoids express the BPV-1 major transforming gene E6. Further, we demonstrate that sarcoid lesions are not associated with high levels of cellular proliferation as assessed by Ki67 expression or with expression of cell cycle regulators CDK-2, cyclin A and p27kip1. Our analysis of p53 shows that a subset of sarcoids are associated with abnormal cytoplasmic and nuclear expression of p53 and that the transactivation function of p53 is compromised in cells with cytoplasmic p53.

Persistent infection with human papillomavirus following the successful treatment of high grade cervical intraepithelial neoplasia.

In a need case-control study, we identified women who were successfully treated for CIN 3. Cases had biopsy proven recurrence, whilst controls remained disease free for at least five years. One hundred and seventy-two women were beta-globin positive at diagnostic and at six-month post-treatment smear (90 controls and 82 cases). Thirty-nine cases (47.6%) were HPV16/18 positive at biopsy or follow up smear and 14 (17.1%) of 82 were positive at both. Of the controls, 37 (41.1%) were HPV positive at biopsy or smear with (3.3%) positive at both. The unadjusted OR associated with being HPV positive at both points compared to being HPV negative at both was 8.0 (95% CI 2.13-30.37). The persistence of HPV 16/18 infection following the confirmed eradication of CIN is a highly significant risk factor for recurrence.